Speaker
Description
Feedback in the form of outflows is believed to be a key ingredient in galaxy evolution. In cosmic noon galaxies, outflows have mainly been detected - and extensively studied - in the ionised gas phase. However, it has been surmised that a large fraction of outflowing mass may be in molecular gas form, as suggested by results of luminous but rare AGNs and quasars. To gain insights into the prevalence and impact of molecular gas outflows on galaxy evolution as a whole, we searched for the telltale broad velocity signature in CO line emission, capitalizing on the IRAM/PHIBSS CO survey of 175 typical near-main-sequence star-forming galaxies at 0.5<z<2.6 and using spectral stacking techniques to reach SNRs $> 30$ for the full sample and various physically-motivated subsets. The results suggest that - if present - the molecular gas outflow signature is remarkably weak. Complementary to this, we investigate the spatially resolved CO emission of three z $\sim 2$ galaxies showing prominent ionized gas outflow signatures and find no molecular gas counterpart. We will discuss implications on the molecular outflow properties, galaxy evolution, and future observational work on feedback through outflows at cosmic noon.
